To observe the germistatic and germicidal effects of origanum volatile oil (OVI) on the dysentery bacteria, the abdominal cavity of mice was infected with Shigella sonne (Sh. sonnei) and Shigella flexneri (Sh. flexneri) F2a. After OVI was given to the mice via gastric lavage, the effects of OVI on the infected mice were observed. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) for dysentery bacteria were determined in vitro. The results showed that origanum volatile oil showed obvious protective effect on mice infected with Sh. sonnei and Sh. flexneri F2a and it had germistatic and germicidal effects on dysentry bacteria. We are led to conclude that origanum volatile oil is an effective medicine against the infection of dysentery bacteria.
Anti-Bacterial Agents/*pharmacology ; Dysentery, Bacillary/*microbiology ; Microbial Sensitivity Tests ; Oils, Volatile/*pharmacology ; Shigella flexneri/*drug effects ; Shigella flexneri/isolation & purification ; Shigella sonnei/*drug effects ; Shigella sonnei/isolation & purification

Shigella bacteremia occurs so rarely that blood culture is useless for the laboratory diagnosis of dysentery. S flexneri type 2 was isolated from a blood culture of a 3-year-old boy with clinical diagnosis of dysentery. A stool culture was negative for not only shigella but also other pathogenic bacteria. This was the only shigella-positive blood culture during the last 12 1/2 years although more than 1,200 cases of bacteriologically proven dysentery were encountered. One of the 4 bottles inoculated with 2 blood samples drawn on the 4th day of illness yielded numerous shigella and few Klebsiella pneumoniae colonies on subculture. On admission the patient was a moderately nourished boy with body temperature of 38 degrees C. The leukocyte count was 10,200/microliter with 29% neutrophils. No evidence of septicemia was noted. He was placed on antibiotics and fluid replacement. The patient was discharged in 6 days after full recovery.
Child, Preschool ; Dysentery, Bacillary/microbiology* ; Human ; Male ; Septicemia/microbiology* ; Shigella flexneri/isolation & purification*

OBJECTIVETo understand the biochemical characteristics, virulence genes and pathogenicity of Shigella flexneri Xv isolated in Beijing.

METHODS61 strains of S. flexneri Xv isolated from diarrhea patients in Beijing were systematically determined through biochemical reactions and serological tests. Application of PCR technique in detection of virulence genes on ipaH, sen, virF, ial and pulsed-field gel electrophoresis (PFGE) was used to identify the related characteristics and on rat lung slices to determine its pathogenicity.

RESULTSAll of the S. flexneri Xv could ferment glucose, mannitol, melibiose and arabinose. Using serum agglutination, we found that the antigen structure was (IV: 7, 8). IpaH, sen, virF and ial that carried rates of virulence genes appeared to be 100%, 81.97%, 75.41% and 80.30%, respectively. Among 61 strains of S. flexneri Xv, the PFGE typing of Shigella bacteria could be divided into 25 belt types while the results from rat lung slices showed inflammatory change of Xv.

CONCLUSIONS. flexneri Xv was found that it carried high rate of Shigella virulence genes, exhibiting genetic polymorphism and highly invasive.

Animals ; Humans ; Microbial Sensitivity Tests ; Rats ; Shigella flexneri ; classification ; isolation & purification ; pathogenicity ; Virulence ; genetics

Objective: To analyze the pathogenic surveillance programs and related factors on bacillary dysentery in Beijing, 2008-2017, to provide evidence for the practices of diagnosis, treatment and prevention of the disease. Methods: Analysis was conducted on surveillance data of bacillary dysentery, collected from the surveillance areas of national bacillary dysentery in Beijing. Shigella positive rate of stool samples were used as the gold standard while detection rate of Shigella, diagnostic accordance rate and resistance were computed on data from the surveillance programs. Chi-square test was used to compare the rates and unconditional logistic regression was used to analyze the related factors of Shigella infection. Results: Both the reported incidence rate on bacillary dysentery and detection rate of Shigella in diarrhea patients showed significantly decreasing trend, from 2008 to 2017. The accordance rate of bacillary dysentery was only 7.80% (111/1 423). Shigella sonnei was the most frequently isolated strain (73.95%, 159/215) followed by Shigella flexnery. Results from the multivariate logistic regression of Shigella positive rate revealed that among those patients who were routine test of stool positive vs. routine test of stool positive (OR=1.863, 95%CI: 1.402-2.475), onset from July to October vs. other months'time (OR=7.271, 95%CI: 4.514-11.709) temperature ≥38 ℃vs. temperature <38 ℃(OR=4.516, 95%CI: 3.369-6.053) and age from 6 to 59 years old vs. other ages (OR=1.617, 95%CI: 1.085-2.410), presenting higher positive detection rates of Shigella from the stool tests. The resistant rates on ampicillin and nalidixic acid were 97.57% (201/206) and 94.90% (186/196), both higher than on other antibiotics. The resistant rates on ciprofloxacin (16.33%, 32/196), ofloxacin (9.57%, 11/115) and on amoxilin (15.05%, 31/206) were relatively low. The resistant rate appeared higher on Shigella flexnery than on Shigella sonnei. The proportion of strains with resistance on 3 more drugs, was 30.00%(21/70). Conclusions: The diagnostic accordance rate of bacillary dysentery in Beijing was low, with severe resistance of Shigella. Our findings suggested that clinicians should take multiple factors into account in their practices about epidemiological history, clinical symptom and testing results for diarrhea patients.
Adolescent ; Adult ; Anti-Bacterial Agents/therapeutic use* ; Beijing/epidemiology* ; Child ; China/epidemiology* ; Dysentery, Bacillary/prevention & control* ; Feces/microbiology* ; Humans ; Middle Aged ; Population Surveillance/methods* ; Sentinel Surveillance ; Shigella/isolation & purification* ; Shigella flexneri/isolation & purification* ; Shigella sonnei/isolation & purification* ; Young Adult

OBJECTIVETo develop a rapid and definite diagnostic test of bacterial enteritis caused by pathogenic enterobacteria, the most frequent etiologic agent of infectious enteritis in the world.

METHODSA set of conventional PCR assays were applied to detect and identify salmonella, shigella, and E. coli O157:H7 directly from pure culture and fecal samples. The general primers of pathogenic enterobacteria were located on the uidA gene, which were found not only in E. coli nuclear acid, but also in shigella and salmonella genes. Shigella primer was from ipaH gene whose coded invasive plasmid relative antigen existed both in plasmid and in genome. The primers of salmonella were designed from the 16SrRNA sequence. The primer of E. coli O157:H7 was taken from eaeA gene. Five random primers were selected for RAPD. The detection system included common PCR, semi-nested PCR and RAPD.

RESULTSThis method was more sensitive, specific and efficient and its processing was rapid and simple. For example, the method could be used to specifically detect and identify salmonella, shigella, and E. coli O157:H7, and its sensitivity ranged from 3 to 50 CFU, and its detection time was 4 hours.

CONCLUSIONThis PCR method, therefore, can serve as a routine and practical protocol for detecting and identifying pathogenic microorganisms from clinical samples.

DNA Primers ; DNA, Bacterial ; analysis ; Escherichia coli O157 ; isolation & purification ; Feces ; microbiology ; Humans ; Polymerase Chain Reaction ; Salmonella typhi ; isolation & purification ; Sensitivity and Specificity ; Shigella flexneri ; isolation & purification

To observe the germistatic and germicidal effects of origanum volatile oil (OVI) on the dysentery bacteria, the abdominal cavity of mice was infected with Shigella sonne (Sh. sonnei) and Shigella flexneri (Sh. flexneri) F2a. After OVI was given to the mice via gastric lavage, the effects of OVI on the infected mice were observed. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) for dysentery bacteria were determined in vitro. The results showed that origanum volatile oil showed obvious protective effect on mice infected with Sh. sonnei and Sh. flexneri F2a and it had germistatic and germicidal effects on dysentry bacteria. We are led to conclude that origanum volatile oil is an effective medicine against the infection of dysentery bacteria.
Animals ; Anti-Bacterial Agents ; pharmacology ; Dysentery, Bacillary ; microbiology ; Female ; Male ; Mice ; Microbial Sensitivity Tests ; Oils, Volatile ; pharmacology ; Shigella flexneri ; drug effects ; isolation & purification ; Shigella sonnei ; drug effects ; isolation & purification

OBJECTIVETo know the molecular characteristic of Shigella flexneri 4c isolates from patients in two food-poisoning outbreaks and one sporadic diarrhea case in Hangzhou, China.

METHODSS. flexneri isolates from patients in two food-poisoning outbreaks (outbreak 1 and outbreak 2, n = 13 and n = 12, respectively) and one sporadic diarrhea patient (n = 1) in Hangzhou during 2003 and 2005 were serotyped. Antibiotic resistances of these isolates were measured by the Kirby-Bauer method. Invasive plasmid antigen gene ipaH was examined by PCR. Pulse field gel electrophoresis (PFGE) was performed for molecular typing.

RESULTSIn outbreak 1, all 13 isolates were S. flexneri 4c, of them 6 isolates tested were quite different in PFGE patterns with dice coefficient from 0.78 to 0.92. In outbreak 2, 10 isolates were S. flexneri 4c and 2 isolates were S. flexneri X, however their PFGE patterns were almost identical (dice coefficient > 0.8). Compared to the two outbreaks isolates, the sporadic isolate was demonstrated with a distinct PFGE pattern (dice coefficient < 0.8). The antibiotic resistance patterns with 14 kinds of antibiotics had a little difference among the isolates from outbreak 1, outbreak 2 and sporadic diarrhea patient, but the same pattern was found among 10 isolates of S. flexneri 4c and 2 isolates of S. flexneri X from outbreak 2.

CONCLUSIONSPFGE might distinguish the isolates from these two outbreaks and the sporadic diarrhea patient. Some differences in PFGE patterns, serotypes and antibiotic resistance patterns might occur among S. flexneri 4c isolates during an outbreak.

Bacterial Typing Techniques ; methods ; Diarrhea ; epidemiology ; microbiology ; Disease Outbreaks ; Electrophoresis, Gel, Pulsed-Field ; Foodborne Diseases ; epidemiology ; microbiology ; Humans ; Microbial Sensitivity Tests ; Shigella flexneri ; classification ; drug effects ; isolation & purification

BACKGROUND: Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with antibiotics is recommended for shigellosis, but the options are limited due to globally emerging resistance. This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of Shigella in China. METHODS: We studied the antimicrobial resistance profiles of 308 Shigella spp. strains (260 S. flexneri, 40 S. sonnei, 5 S. boydii, and 3 S. dysenteriae) isolated from fecal samples of patients (age, from 3 months to 92 yr) presenting with diarrhea in different districts of Anhui, China. The antimicrobial resistance of strains was determined by the agar dilution method according to the CSLI guidelines. RESULTS: The most common serogroup in the Shigella isolates was S. flexneri (n=260, 84.4%), followed by S. sonnei (n=40, 13.0%). The highest resistance rate was found for nalidixic acid (96.4%), followed by ampicillin (93.2%), tetracycline (90.9%), and trimethoprim/sulfamethoxazole (80.8%). Among the isolates tested, 280 (91.0%) were multidrug resistant (resistant to > or =2 agents). The most common resistance pattern was the combination of ampicillin, tetracycline, and trimethoprim/sulfamethoxazole (70.8%). Resistance to ampicillin and tetracycline were more common among S. flexneri than among S. sonnei isolates. CONCLUSIONS: S. flexneri is predominant in Anhui, China, and its higher antimicrobial resistance rate compared with that of S. sonnei is a cause for concern. Continuous monitoring of resistance patterns is necessary to control the spread of resistance in Shigella. The recommendations for antimicrobial treatment must be updated regularly based on surveillance results.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Ampicillin/pharmacology ; Anti-Infective Agents/*pharmacology ; Child ; Child, Preschool ; China ; Drug Resistance, Bacterial/drug effects ; Dysentery, Bacillary/*diagnosis/microbiology ; Feces/microbiology ; Humans ; Infant ; Microbial Sensitivity Tests ; Middle Aged ; Nalidixic Acid/pharmacology ; Shigella/*drug effects/isolation & purification ; Shigella flexneri/drug effects/isolation & purification ; Shigella sonnei/drug effects/isolation & purification ; Tetracycline/pharmacology ; Time Factors ; Trimethoprim-Sulfamethoxazole Combination/pharmacology ; Young Adult

We report a recent case in which ciprofloxacin-resistant Shigella flexneri was isolated from a 23-yr-old female patient with a history of travel to India. Prior to her admission to our internal medicine department, she experienced symptoms of high fever and generalized weakness from continuous watery diarrhea that developed midway during the trip. S. flexneri was isolated from the stool culture. Despite initial treatment with ciprofloxacin, the stool cultures continued to show S. flexneri growth. In the susceptibility test for antibiotics of the quinolone family, the isolate showed resistance to ciprofloxacin (minimum inhibitory concentration [MIC], 8 microg/mL), norfloxacin (MIC, 32 microg/mL), ofloxacin (MIC, 8 microg/mL), nalidixic acid (MIC, 256 microg/mL), and intermediate resistance to levofloxacin (MIC, 4 microg/mL). In molecular studies for quinolone resistance related genes, plasmid borne-quinolone resistance genes such as qnrA, qnrB, qnrS, aac(6')-Ib-cr, qepA, and oqxAB were not detected. Two mutations were observed in gyrA (248C-->T, 259G-->A) and 1 mutation in parC (239G-->T). The molecular characteristics of the isolated S. flexneri showed that the isolate was more similar to the strains isolated from the dysentery outbreak in India than those isolated from Korea.
Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics/metabolism ; Drug Resistance, Bacterial/drug effects ; Dysentery, Bacillary/microbiology ; Feces/microbiology ; Female ; Humans ; India ; Mutation ; Quinolones/*pharmacology ; Shigella flexneri/drug effects/*isolation & purification/metabolism ; Travel ; Young Adult

OBJECTIVETo investigate class I integron of Shigella flexneri, its prevalence in children, and its relation to bacterial resistance to antimicrobial agents.

METHODSTotally 51 strains of Shigella flexneri were isolated from fecal samples of children suffering from bacterial diarrhea seen between June 2004 and November 2004 at Children's Hospital of Fudan University. Polymerase chain reaction (PCR) was employed to amplify various integron markers, including intI1, gene cassette region and 3' conserved region of class I intrgron; susceptibility of Shigella flexneri strains to 7 antimicrobial agents was determined by K-B (Kriby-Bauer) method.

RESULTSForty-six strains of Shigella flexneri had intI gene with a positive rate of 90.2% (46/51); 24 strains of Shigella flexneri were positive for qacEDelta1-sul1, the positive rate was 47.1% (24/51); proportion of the isolates positive for all the three regions of class I integron was 43.1% (22/51); 46 strains of intI positive Shigella flexneri were all positive for ant (3'')-I. Among 46 strains of intI positive isolates, proportions of the isolates positive and negative for qacEDelta1-sul1 were 47.8% (22/46) and 52.2% (24/46), respectively. In the class I integron positive Shigella flexneri, the resistance rates of ampicillin (chi(2) = 10.13, P < 0.01) and chloramphenicol (chi(2) = 19.97, P < 0.01) were significantly higher than those in the class I integron-negative group.

CONCLUSIONSClass I integron was detected in 90.2% of Shigella flexneri in children; carriage of class I integron is related to antimicrobial resistance of Shigella flexneri.

Anti-Bacterial Agents ; pharmacology ; Child ; DNA, Bacterial ; genetics ; Diarrhea ; microbiology ; Drug Resistance, Bacterial ; genetics ; Dysentery, Bacillary ; drug therapy ; microbiology ; Feces ; microbiology ; Humans ; Integrons ; drug effects ; genetics ; Polymerase Chain Reaction ; Retrospective Studies ; Shigella flexneri ; drug effects ; genetics ; isolation & purification